The present invention relates to a wiring structure for electric wirings in a motorcar. The present invention also relates to a junction structure to be used in the case of connecting wire harnesses with each other by means of connectors.
Electric wirings in a motorcar are distributed normally from a battery disposed within an engine room through a relay box provided in the proximity of the battery to respective devices disposed on the outdoor side or on the indoor side. It is a common practice in the prior art that the wirings to the indoor side is distributed by bundling the cords to be distributed to the respective devices on the indoor side and making the bundle of cords pass through a bore drilled in a partition wall separating the outdoor side and the indoor side from each other.
However, the number of the cords to be distributed to the indoor side is so many that it was troublesome to make these cords pass through the bore provided in the partition wall and lead them to a relay box. Moreover, the bundled cords would have an unexpectedly large diameter as a whole, hence the bore provided in the partition wall for making the bundle pass therethrough also has a large diameter, and it was difficult to seal the passing portion.
For the purpose of connecting wirings, generally connectors are employed. In the connection by means of connectors, by mutually fitting a pair of connectors having connecting elements, respectively, to each other, the respective connecting elements are connected to each other. For instance, a structure of such type of connectors is disclosed in Laid-Open Japanese Utility Model Specification No. 48-23367 (1973). In this connector structure, connecting elements provided in one connector are mere protrusions, while connecting elements provided in the other connector have fitting slots formed therein, and the respective connecting elements are connected to each other by the above-mentioned protrusions being inserted and fitted in the aforementioned slots.
While it can be done easily with a weak force to join and separate a pair of connectors to and from each other when the number of the connecting elements to be inserted and fitted is small, when the connecting elements are provided so many, the force required for the joining and separation would become large as a result of summing up, and so, they cannot be joined and separated in a simple manner. When one of the connector is fixed on a support plate or the like a large stress would be applied to the support plate upon joining or separation, and hence, there was a problem because the support plate may be damaged.
In addition, if the respective connectors are not exactly joined, the protrusions forming the connecting elements of one connector would not be inserted and fitted to the fitting slots forming the connecting elements of the other connector, and so, either electrical connection therebetween would not be made or faulty connection would be made. Moreover, sometimes the connecting elements would be damaged or would give damage to other portions.